The bicycle is a common mode of transportation and recreation. A bicycle is powered by a rider, who pushes down on foot pedals to engage a chain that drives the rear wheel. The foot pedal is an important contact point on the bicycle for two reasons. First, the pedal provides the cyclist with stability during riding, and second, it acts as the component through which the cyclist's exertion drives the rear wheel. Therefore, it is important that the pedal provide both of these functions.
A traditional pedal type is the platform pedal. This system is commonly used by many beginning riders, as well as by BMX and downhill riders. The platform pedal provides a stable contact point for the rider to engage the chain. Some pedals have studs on the surface which provide some traction to help keep the rider's feet in place. However, the rider's foot is not mechanically connected to the pedal, and so the rider is only able to supply force during the down stroke. Additional power would be supplied if the rider is able to exert force during both the down stroke and the up stroke.
To this end, a variety of bike pedals assist the rider in securing his feet on the pedal, allowing the rider to supply force during the down and up strokes. A commonly used system is the clipless pedal, which allows for the rider's shoe to mechanically clip into the bike pedal. This system is used by mountain bikers and road cyclists, and allows for greater stability as well as the ability to supply force through the full stroke. Another common system is the toe clip, which is a plastic or metal frame into which the rider's shoe slides for stability. This system is commonly used by riders who want some stability, but are afraid to have the complete fixation that the clipless pedal provides. This system also allows the rider to supply force through the full stroke.
Often a rider who is inexperienced in the usage of clipless pedals will find himself unable to clip out when his bike is falling over. Riders who have clipless pedals can describe their crash experiences when they first were learning to clip out, and have scars to show for it. It is due to this commonality of crashes that there exists a large fear of using clipless pedals among beginner and intermediate riders, notwithstanding the advantages.
What is needed is an intermediate bicycle pedal that features the advantages of the clipless pedals, in that the rider's feet are stably planted on the pedals, and also allow the rider to exert force during both the up and down strokes. At the same time, the pedal should allow the rider to easily and readily disconnect from the pedal to assuage any fears and limitations of releasing from the pedal.
Magnetic pedals have been developed to provide a pedal that allows the rider's feet to be stably planted on the pedal, and also provide enough attraction for the rider to exert force through the full stroke. For example, U.S. Pat. No. 588,038 was an early design for a magnetic bike pedal with a magnet in the bike pedal and a metal plate or magnet attached to a cyclist's shoe. U.S. Pat. No. 5,704,256 discloses a magnetic bike pedal that includes a ramp located on the pedal that allows the cyclist to disengage the magnetic field by using a rotating movement. However, there remains a need for a means to allow a rider to control the degree of magnetic attraction between the pedal and the shoe. What is needed is a magnetic bicycle pedal that can be modified by the rider to fit his changing demands.